Mamie Gummer Engaged to Stage Actor Ben Walker

Stage actor Ben Walker, 27, got on one knee to propose to his longtime girlfriend Gummer, 25, "They're all very happy ... we're very, very smiley," Gummer remarked to People about her family's reaction to the news. Her father is sculptor Don Gummer.

The acting couple met while performing in Les Liaisons Dangereuses on Broadway and started dating a year and a half ago. "He was the Keanu to my Uma," Gummer told People. "We were kind of pals first. It was a drawn-out thing."

Les Liaisons Dangereuses was nominated for five Tony Awards including Best Revival of a Play and Best Actor in a Play (Ben Daniels). Katrina Lindsay won a Tony Award, Outer Critic's Circle Award and a Drama Desk Award for Outstanding Costume Design and Scott Pask won a Drama Desk Award for Outstanding Set Design. Ben Daniels was awarded a Theatre World Award for his role as Le Vicomte de Valmont. Les Liaisons Dangereuses was nominated for nine Outer Critic's Circle Awards, three Drama League Awards and two Drama Desk Awards.